260-2017-01-30

Rick Gilmore
2017-02-08 08:43:58

Today's topics

• Neuroanatomy
  • Forebrain
  • Spinal cord
  • Cranial nerves
  • Autonomic nervous system (ANS)

Organization of the brain

Organization of the brain

Basal ganglia

• Skill and habit learning
• Sequencing of movement
• Example: Parkinson’s Disease

Basal ganglia

Basal ganglia

• Striatum
  • Dorsal
    • Caudate nucleus
    • Putamen
  • Ventral
    • Nucleus accumbens (NAcc)

Basal ganglia

• Globus pallidus
• Subthalamic nucleus
• Substantia nigra (in tegmentum)

Hippocampus

• From Greek for "sea horse"
• Immediately lateral to lateral ventricles
• Memories of specific facts or events, spatial locations
• Implicated in Alzheimer's Disease
• Fornix projects to hypothalamus
• Mammillary bodies

Hippocampus

Amygdala

• “almond”
• Physiological state, behavioral readiness, affect
• NOT the fear center! (LeDoux 2015).

Cerebral Cortex

• Cerebral hemispheres
• Groove (sulcus or sulci)
• Bumps (gyrus or gyri)
• Grey vs. white matter
• Lobes

Cortical Gyri -- Lateral

Cortical Gyri -- Medial

Grey vs. White Matter

• Grey matter
  • Cell bodies, dendrites, axons, glia, vessels
• White matter
  • Mostly axons (covered in myelin)

Lobes of the cerebral cortex

• Frontal
• Temporal
• Parietal
• Occipital
• Related to cranial bones of the skull

Rotating image of cranial bones.

Landmarks of the cortex

Medial longitudinal fissure (longitudinal fissure)

Lateral sulcus/fissure

Central sulcus

Representative interhemispheric fiber tracts in the cortex

• Connect left and right hemispheres
• Corpus callosum
• Anterior, Posterior Commissures

Corpus callosum

Anterior, Posterior Commissures

Lobes of the Cerebral Cortex

Frontal lobe

• Where is it?
  • Anterior to central sulcus
  • Superior to lateral fissure
  • Dorsal to temporal lobe

Frontal lobe

• What does it do/contain?
  • Primary motor cortex (M1)
  • Pre-central gyrus (pre/anterior to central sulcus)

Image of pre and post-central gyri from Wikipedia.

Frontal lobe

• What does it do/contain?
  • Prefrontal cortex
    • Planning, problem solving, working memory...?
  • Anterior cingulate cortex (ACC)
  • Primary olfactory cortex
  • Gustatory cortex

Cingulate Gyrus

Temporal lobe

• Where is it?
  • Ventral to frontal, parietal lobes
  • Inferior to lateral fissure

Temporal lobe

• What does it do/contain?
  • Primary auditory cortex (A1)
  • Object, face recognition
  • Amygdala, hippocampus
  • Storage of memories about events, objects
  • Olfactory cortex

Parietal lobe

• Where is it?
  • Caudal to frontal lobe
  • Dorsal to temporal lobe
  • Posterior to central sulcus

Parietal lobe

• What does it do/contain?
  • Primary somatosensory cortex
  • Perception of spatial relations, action planning

Post-central gyrus

• Post-central -> "posterior to" central sulcus
• Primary somatosensory cortex (S1)

Image of pre and post-central gyri from Wikipedia.

Occipital lobe

• Where is it?
  • Caudal to parietal & temporal lobes
• What does it do/contain?
  • Primary visual cortex (V1)

Visual Cortex

Insular cortex (insula)

• Where is it?
  • medial to temporal lobe
  • deep inside lateral fissure

Insula

Insula

• What does it do/contain?
  • Primary gustatory cortex
  • self-awareness, interpersonal experiences, motor control

Lobes, landmarks, areas

Lobes, landmarks, areas

Lobes, landmarks, areas

Brodmann Areas

• Korbinian Brodmann
• Cytoarchitectonic differences in cerebral cortex

Brodmann Areas

Brodmann Areas

Spinal cord

• Rostral/Caudal axis
  • Spinal column w/ vertebrae
  • Cervical (8), thoracic (12), lumbar (5), sacral (5), coccygeal (1)
  • Spinal segments & 31 nerve pairs
  • Cauda equina

Spinal cord

Spinal cord

• Organization of the spinal cord
  • Dorsal/Ventral
    • Dorsal root (sensory)
    • Ventral root (mostly motor)
  • Grey (interior) vs. white matter (exterior)

Organization of the PNS

• Somatic division

• Autonomic division

• Cranial nerves

• Spinal nerves

Cranial nerves

• Afferents (input), efferents (output), or mixed
• Innervate head and neck
• Olfactory (I), optic (II), (VIII) auditory, vagus (X), etc.
• Spinal nerves

Cranial nerves

Autonomic nervous system

• CNS & PNS components
• Controls "vegetative functions""
  • Limited voluntary control
• Two divisions
  • Sympathetic
  • Parasympathetic

ANS

Sympathetic division

• Prepares body for action
• "Fight or flight""
• Spinal cord
  • ganglion chain along spinal column to End organs
• NTs
  • Preganglionic: ACh
  • Post: NE

Parasympathetic division

• Para -> "around"
• Restorative function
• "Rest & digest"
• Spinal cord -> ganglia near end organs -> end organ
  • NT: ACh

References

LeDoux, Joseph. 2015. “The Amygdala Is NOT the Brain’s Fear Center.” Psychology Today. https://www.psychologytoday.com/blog/i-got-mind-tell-you/201508/the-amygdala-is-not-the-brains-fear-center.